Wrist watch movement having central and eccentric seconds hand arbors



p 1.965 v. STORZ 3,208,210

WRIST WATCH MOVEMENT HAVING CENTRAL AND ECCENTRIC SECONDS HAND ARBORS Filed Oct. 7, 1963 #1 IIIII V77][E777 7V// //JV ///|V////// 8/ 11 L D L2 (3 INVENTOR- VIKTO'R 'STORZ AGENT United States Patent "ice WRIST WATCH MOVEMENT HAVING CENTRAL AND ECCENTRIC SECONDS HAND ARBORS Viktor Storz, Schwenningen (Neckar), Germany, assignor to Kienzle Uhrenfabriken A. G., Schwenningen (Neckar),

Germany, a corporation of Germany Filed Oct. 7, 1963, Ser. No. 314,124 4 Claims. (Cl. 58-59) This invention relates to wrist or strap watches which can be selectively provided with central or eccentric second hands and so that either second hand pinion is in the power train.

In the case of Wrist watches it is desirable to be able to provide the same basic clockwork or movement with either a central or an eccentric second hand. The central second hand pinion or arbor should lie in the power train. The possibility of the suppressing or retarding of this arbor, if it lies outside the power train, is undesirable since the retarding torques are variable and, as the torques increase they constitute an even greater source of error. It has previously been proposed to have the central second hand arbor in the power train, and several embodiments of this conception have been attempted.

Onesuch embodimentis the widely knownconstruction in which the spring barrel drives the minute arbor with the minute wheel situated in the center of the watch, the minute wheel, in turn, driving the intermediate wheel. In a movement provided with a central second hand, the power flow g'oes'from the first intermediate wheel fast on the intermediate pinion to the central second hand, and from there through a loose second intermediate wheel on the intermediate arbor to an eccentrically situated pinion turning 1 rpm. The minute arbor is bored through longitudinally and bearingly mounted in the front workplate and a supplementary bridge, as described in Flume- Schlussel (1955) page 16. The disadvantages of this construction are well known: The supplementary bridge and the long bore through the minute arbor are expensive 'to provide. By not having the bore exactly in alinement,

the second hand arbor can Wander or rub against something. By having the minute wheel located in the watch center the hair spring and minute wheel disturb each other and produce an appreciable source of error. The overall thickness of such a movement is large. As shown in Swiss Patent No. 348,926, the thickness is determined by the sum of those of the spring barrel, the minute wheel and the double intermediate wheels. Because of these objections other constructions were sought.

In the French Patent No. 1,126,161 the spring barrel drives the central minute pinion and this pinion drives an auxiliary wheel which actuates an eccentrically located minute arbor having a minute wheel actuated by the intermediate wheel through a pinion. This intermediate wheel can engage either with the central second hand pinion or the eccentrically located second hand pinion. Whichever second hand wheel is so used drives the escapement wheel. The arbor for the eccentrically located second hand extends through the longitudinally bored minute arbor, that for the central second hand extends in the bore of the central minute pinion. Advantages of this construction as against that previously described are not obtained, for the construction again requires the second hand arbor running in long bores, and a supplementary bridge for the bearing of the minute arbor is necessary. Therefore the movement thickness is at least as great as the sum of the thickness of the spring barrel and the two second hand wheels.

A further development in this art is shown in Swiss Patent 323,377 in which the eccentrically located minute arbor is so shifted that a bore through this arbor in the 3,208,210 Patented Sept. 28, 1965 case of an eccentrically located second hand is not necessary. Furthermore, an additional bridge for the bearings of this arbor can be omitted. Yet the movement thickness of this construction cannot be made small. A supplemental bridge for the central minute pinion is necessary, as is a long bore therethrough. The danger of the rubbing of the central second hand wheel and the hair spring still remains.

It is further known that the spring barrel may drive an eccentrically located minute arbor whose minute wheel meshes with the pinion of the intermediate wheel. The intermediate wheel can here either engage with the pinion of an eccentrically located second hand or the pinion of a central second hand, each having a wheel. Either one of the second hand wheels drives the escapement wheel. Costly longitudinal boring through pinions is not used here. The movement thickness is determined by the barrel, the minute wheel and the second hand wheel and is consequently, again, relatively great. There remains also the large second hand wheel in the middle that can come in rubbing contact with the hair spring. It is well to note the additional disadvantage of the existing restricted space for the movement, especially for the balance wheel. A desirably large balance wheel cannot be used here without the movement having a relatively great diameter.

The present invention on the other hand provides the construction and the advantages set forth next below.

The barrel actuates an eccentrically located minute pinion whose minute wheel drives a first intermediate wheel arbor. In the case of a central second hand, the first intermediate wheel, fast on said arbor, engages with the pinion of the central second hand, which pinion, for its part, engages with a second intermediate wheel loose on the arbor. This second intermediate Wheel drives the eccentrically located second hand arbor whose wheel in turn drives the escapement wheel. Should the movement 'be fitted with an eccentric second hand, the loose intermediate wheel may be omitted. The first wheel, fast on the intermediate arbor, engages then directly with the pinion of the eccentrically located second hand arbor.

In this construction the second hand is always in the power train. Supplementary bridges for the mountings of bearings of supplementary gearing, minute arbors, etc. are not necessary. Boring through minute arbors is not needed and there is suificient space for a large balance wheel, since all Wheel arbors are located on the same half of the work plates, with no crowding. In the central part there is no large minute or second wheel; the hair spring therefore is not cramped. As a result, the thinness of the movement is limited only by the barrel and the minute wheel.

Either second hand pinion can be actuated through an eccentric minute wheel by means of a known double intermediate wheel. The barrel permits a favorable proportionate size of the main spring. The space between the movement plates, except for the thickness of the minute wheel, can be used for the barrel so that the main spring may be relatively wide. By having a wide spring the difference in spring moments at a fully wound state and after a 24-hour run-down is slight.

In the drawing:

FIG. 1 shows a schematic side view of the movement train with the arbors of the movement all shown as though they lay in a single plane, for purposes of clarity in depicting the limit-s of minimum thickness of the works,

FIG. 2 shows a schematic representation of the movement train as shown in FIG. 1, but the actual positions of the various train elements, and

FIG. 3 shows a diametric sectional view of the movement represented in FIG. 2.

The barrel 1 drives a minute arbor 2 whose minute wheel 3, fast on the arbor, engages with a pinion 4 fast on an intermediate arbor 4. An upper or first intermediate wheel Sis fast on the arbor 4 and engages a pinion 6 on a central second hand spindle 6 which can carry a suitable sweep second hand (not shown). This spindle is bearingly mounted for turning on the movement plates 7 and 8 and transverse thereto.

The power then goes from the pinion 6, wide enough to engage two wheels, to a lower or second intermediate wheel 9 of the same size as wheel mounted for slip turning on the arbor 4. The loose wheel 9, being driven by the pinion 6, however turns practically with the fixed wheel 5 and the loose wheel engages the pinion 10 of the eccentric second hand arbor 10.

Details of the arrangement of arbors 2, 4, 6 and 10 are shown in FIG. 3 and their distribution in FIG. 3. In FIG. 1 phantom lines to the left of pinion 6 represent planar positions of the wheels 5 and 9 and the wheels extent with respect to the pinion 10 as can be understood from FIG. 2.

The arbor 10 carries a wheel 11 which drives an escapement wheel 12 operating in a conventional manner.

It is to be noted that wheels 5 and 9 are so spaced with respect to the pinion 10 that the latter is engaged by the loose wheel 9 but not by the fixed wheel 5.

If the movement is to have an eccentric second hand it may be mounted on the spindle 10 without change as far as the movement is concerned. As an alternative, the arbor 6 and its pinion may be omitted, as may the wheel 5, and the wheel 9 made fast on arbor 4.

The hand works consisting of a cannon pinion 13, hour wheel 14 and change gear 15 are actuated by means of a gear 16 frictionally coupled to the minute arbor 2, the coupling permitting the setting of the watch in a known manner.

The cannon pinion 13 is mounted on a bearing boss 13a provided with a bore through which the central seconds hand spindle passes and the boss serves as a bearing for the cannon pinion 13.

As shown in FIG. 1 the thinness of the movement is is limited only by the barrel and minute wheel 3. The second hand arbors 6 and 10 are always in the power train. The barrel is so large that the main spring can be favorably dimensioned. The central second hand arbor is bearingly mounted between both movement plates, and especially through the front plate by means of a fixed short tube or boss, which in this form of the invention also serves as a bearing for the cannon pinion. need for the usual supplementary bridge.

In FIG. 2 the further advantages of the invention are recognizable. No minute or second hand wheel is present in the roomy space for the balance; the hair spring is not endangered by any wheel. The balance can be as large as may reasonably be desired, for the arbors of the gear train are all in less than a diametric half of the movement. The train is clearly not crowded and this is due to the eccentrically located minute arbor and double intermediate wheel.

The invention claimed is:

1. A round watch movement for having either a central or eccentric seconds hand afiixed thereon comprising two spaced flat movement plates, a main spring barrel between the plates; an eccentric minute arbor driven 'by the barrel and having a minute wheel overlapping a part of the barrel; an intermediate arbor and pinion driven by the minute wheel, theintermediate arbor carrying two equally shaped intermediate wheels, one turnable and the other fixed, with respect to said intermediate arbor a central seconds hand arbor having a wide pinion thereon and engaging said intermediate wheels; and an eccentric seconds arbor carrying fast thereon a pinion meshing with the turnable wheel, and escapement means driven from the said eccentric seconds arbor, one of said plates being provided with an outwardly projecting bearing boss to receive one end of the central seconds hand arbor therethrough and to serve as a bearing for a cannon pinion thereon to turn about.

2. A watch movement as claimed in claim 1 said central seconds hand arbor being free from radial projections between the plates in excess of radius of the pinion of this arbor.

3. A watch movement as claimed in claim 1 the opposite end of said central seconds hand arbor being bearingly There is no mounted in the other plate and the other mentioned arbors having their respective end-s being bearingly mounted in the two respective flat plates.

4. A watch movement as claimed in claim 3 and free from a supplementary plate between said two fiat plates.

References Cited by the Examiner UNITED STATES PATENTS 2,872,775 2/59 Maine 5 8-5 9 2,981,055 4/61 Froideneaux et a1. 5 85 9 3,138,916 6/64 Beaumann 58.59

FOREIGN PATENTS 335,091 I/ 61 Switzerland.

LEO SMILOW, Primary Examiner. 

1. A ROUND WATCH MOVEMENT FOR HAVING EITHER A CENTRAL OR ECCENTRIC SECONDS HAND AFFIXED THEREON COMPRISING TWO SPACED FLAT MOVEMENT PLATES, A MAIN SPRING BARREL BETWEEN THE PLATES; AN ECCENTRIC MINUTE ARBOR DRIVEN BY THE BARREL AND HAVING A MINUTE WHEEL OVERLAPPING A PART OF THE BARREL; AN INTERMEDIATE ARBOR AND PINION DRIVEN BY THEMINUTE WHEEL, THE INTERMEDIATE ARBOR CARRYING TWO EQUALLY SHAPED INTERMEDIATE WHEELS, ONE TURNABLE AND THE OTHER FIXED, WITH RESPECT TO SAID INTERMEDIATE ARBOR A CENTRAL SECONDS HAND ARBOR HAVING A WIDE PINION THEREON AND ENGAGING SAID INTERMEDIATE WHEELS; AND AN ECCENTRIC SECONDS ARBOR CARRYING FAST THEREON A PINION MESHING WITH THE TURNABLE WHEEL, AND ESCAPEMENT MEANS DRIVEN FROM THE SAID ECCENTRIC SECONDS ARBOR, ONE OF SAID PLATES BEING PROVIDED WITH AN OUTWARDLY PROJECTING BEARING BOSS TO RECEIVE ONE END OF THE CENTRAL SECONDS HAND ARBOR THERETHROUGH AND TO SERVE AS A BEARING FOR A CANNON PINION THEREON TO TURN ABOUT. 